fixed cache clearing of categories upon creation / update

Author: Oaphi

app/controllers/categories_controller.rb

@@ -47,9 +47,7 @@ def create
       AuditLog.admin_audit(event_type: 'category_create', related: @category, user: current_user,
                            comment: "<<Category #{before}>>")
       flash[:success] = 'Your category was created.'
-      Rails.cache.delete "#{RequestContext.community_id}/header_categories"
-      Rails.cache.delete 'categories/by_lowercase_name'
-      Rails.cache.delete 'categories/by_id'
+      clear_categories_cache
       redirect_to category_path(@category)
     else
       flash[:danger] = 'There were some errors while trying to save your category.'
@@ -69,9 +67,7 @@ def update
       AuditLog.admin_audit(event_type: 'category_update', related: @category, user: current_user,
                            comment: "from <<Category #{before}>>\nto <<Category #{after}>>")
       flash[:success] = 'Your category was updated.'
-      Rails.cache.delete "#{RequestContext.community_id}/header_categories"
-      Rails.cache.delete 'categories/by_lowercase_name'
-      Rails.cache.delete 'categories/by_id'
+      clear_categories_cache
       redirect_to category_path(@category)
     else
       flash[:danger] = 'There were some errors while trying to save your category.'
@@ -207,6 +203,12 @@ def set_list_posts
     @posts = @posts.paginate(page: params[:page], per_page: 50).order(sort_param)
   end
 
+  def clear_categories_cache
+    Rails.cache.delete 'header_categories'
+    Rails.cache.delete 'categories/by_lowercase_name'
+    Rails.cache.delete 'categories/by_id'
+  end
+
   # Updates last visit cache for a given category
   # @param category [Category] category to update
   # @return [Boolean] whether the cache entry is deleted